Counterbalance for vertically sliding doors



Dec. 1, c c MOLER COUNTERBALANCE FOR VERTICALLY SLIDING DOORS FiledMarch 8, 1951 2 Sheets-Sheet 1 IN V EN TOR.

Dec. 1, 1953 c, Q MQLER 3 COUNTERBALANCE FOR VERTICALLY SLIDING DOORSFiled March 8, 1951 2 SheetsSheet 2 IN V EN TOR.

Patented Dec. 1, 1953 COUNTERBALANCE FOR VERTICALLY SLIDING DOORSCharles C. Moler, Hartford City, Ind., assignor to Overhead DoorCorporation, Hartford City,

Application March 8, 1951, Serial No. 214,575

7 Claims.

This invention relates to improvements in counterbalance for verticallysliding doors.

The principal objects of this invention are:

First, to provide an economical and simplified counterbalance of thecoiled torsional spring type for vertically sliding doors.

Second, to provide counterbalance structure having a minimum number ofparts in which the spring supporting structure coacts with the drum of adoor supporting cable to maintain the drum in proper alignment.

Third, to provide a novel and inexpensiv form of cable drum which iseasily mounted and connected to a coiled counterbalance spring.

Fourth, to provide novel means for connecting a coiled torsional springto the cable drum of a door counterbalancing structure.

Fifth, to provide a counterbalance structure of the torsional coilspring variety for vertically sliding doors which is easily adjusted toproper tension and which is sturdy and long lived in operation.

Other objects and advantages of my invention will be apparent from aconsideration of the following description and claims.

The drawings, of which there are two sheets, illustrate the preferredform of my counterbalance structure operatively associated with a doorof the vertically sliding type.

Fig. 1 is a fragmentary inside elevational view of a vertically slidingdoor with my counterbalance structure operatively connected thereto.

Fig. 2 is an enlarged elevational view of the counterbalance structurepartially broken away in longitudinal cross section along the plane ofthe line 2-2 in Fig. 1.

Figure 3 is a fragmentary perspective view of the end of thecounterbalance spring and its support ready to be connected to the drumof the door supporting cable.

Figure 4 is a fragmentary cross sectional view through the drumsupporting spindle taken along the plane of the line 44 in Fig. 1.

Figure 5 is an end elevational view of the support and adjustingconnections for the fixed end of the spring.

In Figure 1 I have illustrated portions of a conventional type ofvertically sliding door. These include the door I having supportinghinge and guide brackets 2 secured along the edge thereof. The guidebrackets carry pins 3 for supporting rollers in the guide track 4 as iscommon in doors of this type, and one of the brackets 2 carries alaterally extending support flange or bracket 5 to which acounterbalancing suspension cable 6 is 2 attached. The cable extendsupwardly to the counterbalancing structure indicated generally at I tosustain most of the weight of the door and facilitate its opening andclosing motion.

The counterbalancing structure I which constitutes my invention consistsof a pair of flanged supporting brackets 8 and 9 which are fixedlysecured to the wall in laterally spaced relationship above the door I.The major elements of the counterbalance structure include a drum 10 fortaking up and paying out the cable 6, a coiled torsional spring I Iwhich is attached to the drum to store up energy as the door is loweredand thus counterbalances the weight of the door, an anchor block 2 foradjustably supporting the fixed end of the spring II, and an innerwooden spacing core it which prevents buckling of the spring iiintermediate of its ends. The drum l0 and the right end of thecounterbalance structure was rotatably supported from the rig-ht bracket9 by a stub shaft or spindle M and the left end of the structure and theanchor block l2 are supported from the left bracket 8 by a pin [5.

Considering the construction of the drum [0 and its connection to thespring H in greater detail it will be noted that the drum includes anouter cylindrical rim portion [6 which is spirally grooved to take upand pay out the cable in neat coils. The interior portion of the drumconsists of a Wheel-like disc ll formed integrally with the rim andapertured at the center to pass the spindle Hi. The spindle M which isfixedly secured to the bracket 9 by the nut I8 is provided with anannular flange or collar I9 located within the aperture in the disc llof the drum. Fixedly secured at opposite sides of the disc I! are a pairof hub plates 2% which are provided with oppositely and inwardly concavehub flanges 2| projecting radially inwardly of the aperture in the discll. The hub flanges 2| form ways or retainers for a plurality of'ballbearings 22 which are thus retained on opposite sides of the collar l9.Quite obviously the drum l0 and supporting spindle M are initially andpermanently assembled together as a unit by the permanent attachment ofthe hub plate 29 to the disc l1. Rivets 24 secure the elements of thedrum structure together as is best shown in Figure 4.

The disc I! and hub plates 20 of the drum are formed with twodiametrically opposed holes 25 extending completely therethrough to passthe threaded. ends of a pair of anchor pins 26. On their axially innerends the pins 26 are enlarged and provided with transverse bores 2'! sothat the pins may be threaded successively over the right end of thetorsional spring II. Prior to being threaded over the spring H the innerends of the pins 26 are engaged in holes 28 in the opposite ends of alock plate 29 and the plate and 5 pins are thenthreadedonto thespring ina t wist ing motiq igso that theputer endjcoil gijthe sprin 5 retainsthe plate 29 axially while the engagement" of the inner ends of the pins26 within the holes 28 prevents removal of the plate transversely '10 ofthe spring. The plate 29 is'providedwithial central aperture 30 whichpasses the inner end of the spindle I4.

The free or inner end oi the spindle ligi shouldered as at 31 to pressagainst and ex- 15 tend into the center of the spring spacin g co re l3.Sufficient room is provided between the inner hub flange 2| of the drumand the endflpi v the core to pass the anchor plate 29 as is most asseatee 59? fsg p e mixer sle er the ve pins, ,32 serves a diabetesables wh ch i dl y tiirdii li.ahcle 6" 'ifidfyvrapped' aroundthe pina'sf iridi ii the support and po n iiqns, dfof the. spring ittvi'll beno ted. 35 hQi' 'blolckjlz is" rotatable about the s [capable of beingsecured in differdju ted positions by anchor screws ack 8. The anchorblock' isg further so P n v p w a series of radially extendir ig holesor so kets'fii which are adapted to receive;

aspanner wrench 'for rotating the anchor block p ll s rin 1 ,7 r f l t ll eadin e.v s 33 are] inserted to v hold the pag The inner end of therrv di th a bere s 'i alo ask Janis threaded nto the ag 1 ng n forms aspring clutch conj with; l5fwlliich supports theanchor block through the'block linto, the end of g core f3 'so that the pin l 5 core 3; i p 1nd1ej M are mutually selfisirppdrted in: alig merit within the spring l I;The core 13-- befinade :oi wood as shown or inexpensive pi or con'duitfor light weight and'is'not sub; ject ed to any great loads bytheoper'ation er; th kounterbalance"structure. fiesirably'; the end of the;spring i i that engagesthepins ZEisb'ent from the circular shape of"thebody-"o'f' t'he spring as 'at m to prevent 3 the spring from twistingout of the holes 21 shlj'uldfthe nfit'S EZ b'e insufficiently tightened.'Ih' holes] 1 aremaae 'large enough to permit theg'threading ofthe pinsover thebent end of the spring dui'in g assemblybut once the pins areengaged through lthejdrum Iii they will not twfis or'jmri suflicienjtly, to permit unintentional is adi g of th rin oms i e, P ne. iusvl sqr e i ent- 911 w t i aim s. er nd; egree. eere Pr Le ters 1.Spring counterbalance structure for a vertically movable doorcomprising, a pair of my porting brackets adapted to be mounted intransversely spaced relationship above said door, a spindle fixedlysecured to one of said brackets and located to one side of said door, acollar ,on said spindle forming an inner bearing guide, a drum rotatablynounted on sai d spindle aiiddncluding an inner hub portion retainingball bearings on each side of said collar, said drum including aradially extending disc portionl. defining-,- diametrically oppositelocated haiesand an outer cable supporting rim, a pin supp-ortedloy -thepther of said brackets and extending aligiied position toward saidspindle, a spring'supporting core extending between and supported bysaid spindle and said pin, an ancherb'lock rotatabl-y adjustably mountedon rs ai d pir means for securing said block to said other bracket inadjusted position, a coiled tor- Q fi li a ififi la qull l qt9Q? 3 235C" me ii esifis g iq saiiqb eq a h r plate positionedj between thefirst 'and second tui ns of the other end offsai'd spring and havingholes vriht r hree e. n i ent d pfie the sides of said outer tur'nlofsaid sp ringfw ith the center hole passing said spindl anchor'pinshaving theirinr erends received in-the end holes in idanchoriplate andforming transverse ap ertures "thr'dugh; wh1ch the-outer turn of --saidg spring is passed; saidfanchor pins extending;- threugh the holes inthedisc portion; of saiddrum, and nuts on-the other endsof's'aid an chorpins clamping the: outer turnlofsaid springagai nst inne'r' side 'ofs'aiddrum one ofsaid anchor pins and nuts 1 forming anl anchorattachrhent '-for a supporting cable--adapted-to-be coiled aroundsaiddrinn an'd 'adapted-td extend dgwnwardly and ee connected; to saiddoom-"said other end of-said spring having-a hooked tipto'prc'vent saidspring from-twistingout-onen gage'riie nt with said pins.

Z Spring counterbalance structure for--aver-, tic al lymovable-deercomprising; a pairof-sup porting brackets adapted to be1n'ou-ntednitransversely spaced relationship above-said decr a' spindlefixedly secured to one (obsaidehra ckets and located to one Slde Ofisaid doorQarollar on said spindle=-forming-an .-inner-bearing guide, adrum rotatably mounted-.011saidspindlew arid including an -{innen huhportion retaining ball --bearings on each L side 'Jof said collar,said-,- drum including a radially extending-disc--per-- tion definingaghole radially spaced from-ii'its center and an outerca-ble;supportingurimga.pin/ supported by the otheh-ofsaid bracketsandextending toward said spindle; a'.spring support ing core -exten'ding.betweeri an d supportedz by said spindle-and "saidpin, an-anehorblock-wotatably adjustably amounted-on said -pingmeansl for securing said blockto said:other bracketin adjusted position; a coil; spring disposedaround said c'or'e' and havinlglloneendffixed to said block,- an anchorplate-positioned betwee-rnthemfirsts and second turns ofthe other end ofsaid: spring and having halesfor'ined therethrough, one; passing saidspindle and another oppositeethew outer turn of said. spring, wanJanchor- =has/ind; itsilinner' end received inthe; outer hole in saidwee-a e? a e; felt-mi e. t s r e e ur thrcugh hich -the outer turn orsaid-spring is; a se s id eh r, e. n in e e i hole; in said disc portionof said drum a nutonthe other end of said anchor pin clamping the outerturn of said spring against th -ihfiffia? 3. Spring counterbalancestructure for a vertically movable door comprising, a pair of supportingbrackets adapted to be mounted in transversely spaced relationship abovesaid door, a spindle fixedly secured to one of said brackets and locatedto one side of said door, a drum rotatably mounted on said spindle andaxially fixed thereon, said drum including a radially extending discportion defining a hole radially spaced from its center and an outercable supporting rim, a pin supported by the other of said brackets andextending toward said spindle, a spring supporting core extendingbetween and. supported by said spindle and said pin, an anchor blockrotatably adjustably mounted on said pin, means for securing said blockto said other bracket in adjusted position, a coiled spring disposedaround said core and having one end fixed to said block, an anchor pinhaving a transverse aperture through which the outer turn of said springis passed, said anchor pin extending through the hole in said discportion of said drum, a nut on the other end of said anchor pin clampingthe outer turn of said spring against the inner side of said drum.

4. counterbalance structure for a vertically movable door having asupporting cable attached thereto comprising, a pair of brackets fixedlysupported above said door, pins projecting inwardly from said brackets,a spring sup-porting core supported between and aligning the inner endsof said pins, an anchor block rotatably adjustably mounted on one ofsaid pins, a drum rotatably mounted and axially fixed on the other ofsaid pins and adapted to be connected to said cable to wind up the same,a. coil spring sleeved around said core and having one end connected tosaid block, and means including pins passed axially through said drumand connected to the other end of said spring for drivingly connectingsaid drum to said spring, said connecting pins having recesses embracingsaid spring, and clamping nuts on the opposite ends of said pins fromsaid spring for clamping the end of the spring axially against saiddrum, said other end of said spring having a hooked tip to prevent saidspring from twisting out of engagement with said pins.

5. Counterbalance structure for a vertically movable door having asupporting cable attached thereto comprising, a pair of brackets fixedlysupported above said door, pins projecting inwardly from said brackets,a spring supporting core supported between and aligning the inner endsof said pins, an anchor block rotatably adjustably mounted on one ofsaid pins, a drum rotatably mounted on the other of said pins andadapted to be connected to said cable to wind up the same, a coil springsleeved around said core and having one end connected to said block, andmeans connected to the other end of said spring for drivingly connectingsaid drum to said spring, said connecting means having portionsoverlapping the end turn of said spring and clamping nuts for clampingthe end of the spring axially against said drum.

6. Counterbalance structure for a vertically movable door having asupporting cable attached thereto comprising, a pair of brackets fixedlysupported above said door, pins projecting inwardly from said brackets,a spring supporting core supported between and aligning the inner endsof said pins, an anchor block rotatably adjustably mounted on one ofsaid pins, a drum rotatably mounted on the other of said pins andadapted to be connected to said cable to wind up the same, a coil springsleeved around said core and having one end connected to said block, andmeans connected to the other end of said spring for drivingly connectingsaid drum to said spring.

7. counterbalance structure for a vertically movable door having asupporting cable comprising, a drum rotatably mounted and adapted totake up said cable in the elevated position of the door, a coil springmounted in generally coaxial alignment with said drum with one endpositioned adjacent to said drum and with its other end fixed, means forsecuring the free end of said spring to said drum including an anchorpin having a transverse recess through which the end turn of said springextends, said pin extending axially of said drum through a hole providedtherefor in a portion of said drum spaced radially from its axis ofrotation, and a nut threaded on said pin on the opposite end of saiddrum from said spring and clamping the end of said spring against saiddrum.

CHARLES C. MOLER.

References Cited in the file of this patent UNITED STATES PATENTS NumberI Name Date 2,010,214 Braun Aug. 6, 1935 2,201,636 Siess et a1 May 21,1940 2,257,484 Rowe Sept. 30, 1941.

